1 Answer

CKditor4 plugin is equipped with CKEditor V4.2. You can add plugin compatible with CKEditor V4,2 to CKditor4 plugin. First, you should confirm plugin compatibility.
http://ckeditor.com/addons/plugins/all

Check installation method of the target plugin.

Admin > Plugins > CKEditor4 > option

Add things necessary for "Toolbar buttons:" and "Other configuration"

Description method of "Other configuration" is slightly different from config.js.